Lyric discussion by mayucio 

Cover art for Iodine lyrics by Leonard Cohen

This song is about Cohen falling in love with a photographer but not really loving her enough to fully pay attention to her. Iodine salts are used in black and white photography. Hence also the reference to a dark place and a room. Also, failing at love does not necessarily imply sexual incompetence... "love" could also mean establishing a relationship, but that´s just my romantic side talking.